The invention pertains generally to an excavating tool such as, for example, a cutter bit useful for cutting through various earth strata and other materials. More specifically, the invention pertains to a flat cutter bit with a cutting insert having edge preparation.
Various types of cutting assemblies having cutter bits are used for mining, construction and related operations wherein, typically, the cutter bits include a shank for insertion into a tool holder and a forward working portion on the shank for engagement with earth strata, e.g., coal, or mineral formation or other natural materials or the like. An individual insert formed of a hard, wear resistant material is provided on the forward working portion to cut into the earth strata and to enhance the life of the cutter bit as it removes the material.
An example of a cutting assembly having cutter bits that are used for mining and construction operations include a flat cutter tool. These types of cutting tools usually include a plurality of cutter bits mounted on a rotatable disc, rake, chain, barrel or drum, wherein each of the cutter bits include a substantially-flat cutting insert made of a hard material. These substantially-flat cutting inserts are affixed to the forward working end of the cutter bits. However, it has been determined that due to the shape and configuration of the substantially-flat cutter inserts, the cutter inserts do not wear uniformly. This non-uniform wear decreases the overall useful life of the cutting inserts. More particularly, the cutting edge of the substantially-flat cutter inserts have a tendency to chip or break during use due to the shape of the cutting edge.
Accordingly, it would be desirable to provide improved cutting tools that overcome limitations and disadvantages of known such tools. In addition, it would be desirable to provide improved cutter bits that overcome limitations and disadvantages of known cutter bits and that provide for improved wear and efficiency during operation. Furthermore, it would be desirable to provide improved cutting inserts for cutter bits that overcome limitations and disadvantages of known cutting inserts and that provide for improved wear and efficiency during operation.